The prior art utilizes paper web cutters of a rotary type where two cylinders, in rolling contact, carry the respective cutter elements of a cutter and an anvil or the like. The web passes between the two cylinders, and the cutter then shears the paper across its width. In some instances, the cut paper is gripped by one of the rotating cylinders and the cut section is then conveyed away See U.S. Pat. No. 2,797,097.
In that arrangement of the prior art, the concern is with regard to the provision for, and the synchronization of, the cutter and the anvil. That is, they must be provided for in durable metal material which is generally required to be hardened, and the mating between the cutter and the back-up member on the other cylinder must be with extreme precision. These limitations and requirements also result in a restriction on the permissable speed of moving the web of paper.
The present invention improves upon the prior art cutters in that it combines both the conveying and cutting members in the same elements of the conveyor itself, all such that the web is positively held by the conveyor and is also cut while moving at a high speed. This is achieved because the web is simultaneously held on its opposite faces at the same time that it is cut and conveyed forward along its path of movement, and at no time is the web free of the conveyor until it is deposited on a collecting conveyor or the like.
In accomplishing the objective of improving upon the prior art and avoiding the precise requirements of rotary cutters in the way of synchronizing cutter and anvil, the invention provides for two opposed lengths of conveyor belts which engage respective faces of the web for moving the web and for holding the web while it is being cut during its movement. The shearing cutter itself is carried on a moving member which progresses or moves with the forwarding of the web, and the opposed belts retain tension in the web so that it is accurately and cleanly cut, and the belts also retain the cut web for conveying it to the deposit conveyor or the like.
A further improvement of the present invention is with respect to providing two cutters, or assemblies thereof, at two different stations along the path of the moving web, with one of the cutters cutting across the width of the web in only a portion thereof, such as in a perforated type of cut, and with the other cutter at the downstream station cutting the remainder of the web, so that the complete web is finally cut. Still further the present invention provides for only the first of the aforementioned cutter which performs the socalled perforated type of cut, and the web can then be further engaged in its downstream travel to be pulled at a faster speed than the speed at the time it is cut, and that faster pulling speed will cause the web to completely sever across its width through a tearing action of the remainder of the width which is otherwise uncut.
In the present invention, the web of paper is moved at a high speed and is severed across its width at various lengths along the web, and the cut sections of the web can then be deposited on a take-off conveyor, as desired. In accomplishing these objectives, the need for precision cutting elements is obviated, and the prior art problem of dullness and wear of the cutting elements is also avoided.